Recording samples after detecting peak in the receiver

Hi,

I am working on a project(channel response estimation),in which i have
to
start recording the samples after the receiver detects the packet.

Currently i am transmitting a packet using benchmark_tx.py example and
using benchmark_rx.py to receive the packet.

1…Is correlator block implemented in FPGA or in the host software?(for
comparing access code with the received packet code).
2. If i want to implement it on FPGA ,how to start,because i have never
done FPGA programming before.
If there is any workaround please let me know…

Thanks.

On Tue, Mar 26, 2013 at 11:38 PM, john jade [email protected]
wrote:

comparing access code with the received packet code).
Implemented in software. The synchronization loops are all done in the
receiver’s host side (that is, in GNU Radio). Specifically, the access
code is used on framer_sink_1 (see gr-digital/python/pkt.py).

You could redo or copy the framer block into your own where it emits a
“burst” tag with the value pmt::PMT_T when it sees the access code.
You can then tie this directly to the the tagged_file_sink block,
which looks for a tag with key “burst”. When the tag’s value is true
(PMT_T), it will open a new file and save the samples. When it gets a
tag with a value of false (PMT_F), it will close the file. So you’ll
have to have a way to detect the end of the packet, which could just
be knowing how many bits are in a full packet.

  1. If i want to implement it on FPGA ,how to start,because i have never
    done FPGA programming before.

That’s a steep learning curve. As long as your host machine can handle
the bandwidth you need, I wouldn’t go there.

If there is any workaround please let me know…

Thanks.

Tom